function jqlazyload() {
  let temp1 = window.innerHeight || document.documentElement.clientHeight
  let temp2 = document.body.scrollTop || document.documentElement.scrollTop
  let maxShowHeight = temp1+temp2
  $('img').each((i,item)=>{
        if(item.offsetTop>maxShowHeight){
            let real=$(item).css('data-real')
            $(item).css('src',real)}
    })
}